You can have mods that show just the cave systems but most servers will consider that hacking and ban you for it.
The best way to officially map cave systems within survival limits is to constantly look at and record your coordinates (especially Y) then draw a loose sketch on them. It takes a long time but it's the way I do it.
This one in particular isn't a mapping program, it can be achieved by shoving a Glowstone or TNT(or any solid block that you don't suffocate in) into your head with a piston.
My favorite mapper is MCMap, which has the unique feature only mapping caves that have torches in them; in other words, you only see what you have explored (although in vanilla you will see mineshafts and strongholds; I modded their torches out for this reason; I also modded the open source version of MCMap to reduce the area shown around torches to a realistic range).
Here is an example of caves in my world as seen with MCMap, including a zoomed-in view of the area I'm currently exploring (in the lower-right of the full map at the very bottom); notice the area in the lower-right, which is a cave system+mineshaft I've started to explore, with only the areas I've been in so far shown, you can also see where I staircased to the surface when I had to leave to unload what I'd mined:
How did you set Mcmap to only render the caves? I'm using the GUI and I don't see any such option.
It is the "underground" option:
Also, it only actually shows anything if you have placed torches to light them up, which is how I made this animation (you only see the tunnel I made for a railway in areas I later explore; I modified mineshafts to remove/replace their naturally generated torches so they do not render, otherwise you'll see some random bits here and there, and I also modified MCMap itself to reduce the range mapped around a torch to a realistic amount):
I am currently interested in finding a simple way to map my underground network in MC1.8.1
I am aware of such tool like Overviewer but like the name says... it's an overview and not an underground view.
I was thinking of obtaining something like this (found on google):
Any idea where I should digg an answer?
http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-tools/1263598-unmined-2d-mapper
http://unmined.intro.hu/
The guy who built this soft did an amazing job.Maybe it will help some other players
The best way to officially map cave systems within survival limits is to constantly look at and record your coordinates (especially Y) then draw a loose sketch on them. It takes a long time but it's the way I do it.
This one in particular isn't a mapping program, it can be achieved by shoving a Glowstone or TNT(or any solid block that you don't suffocate in) into your head with a piston.
Here is an example of caves in my world as seen with MCMap, including a zoomed-in view of the area I'm currently exploring (in the lower-right of the full map at the very bottom); notice the area in the lower-right, which is a cave system+mineshaft I've started to explore, with only the areas I've been in so far shown, you can also see where I staircased to the surface when I had to leave to unload what I'd mined:
TheMasterCaver's First World - possibly the most caved-out world in Minecraft history - includes world download.
TheMasterCaver's World - my own version of Minecraft largely based on my views of how the game should have evolved since 1.6.4.
Why do I still play in 1.6.4?
How did you set Mcmap to only render the caves? I'm using the GUI and I don't see any such option.
It is the "underground" option:
Also, it only actually shows anything if you have placed torches to light them up, which is how I made this animation (you only see the tunnel I made for a railway in areas I later explore; I modified mineshafts to remove/replace their naturally generated torches so they do not render, otherwise you'll see some random bits here and there, and I also modified MCMap itself to reduce the range mapped around a torch to a realistic amount):
TheMasterCaver's First World - possibly the most caved-out world in Minecraft history - includes world download.
TheMasterCaver's World - my own version of Minecraft largely based on my views of how the game should have evolved since 1.6.4.
Why do I still play in 1.6.4?